I just ran into a problem where Mma lack of dimension on a vector caused
problems. I need to take the matrix product of a matrix with a vector
times its transpose; i.e., (A x) (A x)'
I needed the following Mma syntax to get this
Outer[Times, A . x, A . x], which is ugly but okay. But if Ax is a matrix
instead of a column vector, one needs (A.x) . Transpose[A.x]
Is there a general way to do matrix multiplication in Mma where dimension
is considered? I thought about it briefly, but do not know how to
cope with the fact that one dimensional lists are neither row or
column vectors.
Your help is appreciated.
Phil Miller